On Roman Numerals
Learn the basics of Roman numerals and how to write them, from I (1) to M (1,000) and above. Also, submit an Arabic numeral and click to convert it into its Roman numeral equivalent; or vice versa.
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OOG: the Object Orientation Game - MCM Productions
MCM Productions' first publicly released software application. This 4-in-1 tiling puzzle game for the MS-Windows environment allows players to test their problem solving ability with over 300 puzzles, including Tangrams, Pentominoes, Hexagons and Polyominoes.
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Open Middle - Johnson, Nanette; and Kaplinsky, Robert
"Open middle" problems, hints, and answers, all aligned to the Common Core State Standards (CCSS). Introduced by Dan Meyer, these kinds of math challenges have a "closed beginning," meaning that they all start with the same initial problem; a "closed
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Optical Data School Media
A publisher of math and science programs, including Windows on Math, an activity-based laserdisc and videotape curriculum built around the NCTM standards. Most products are for levels K-8. Find Correlations for Optical Data products to a wide range of
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Overthinking My Teaching - Christopher Danielson
Blog by a community college math teacher "interested in hard questions about teaching." Posts, which date back to July, 2009, have included "Wump hats," "An unnoticed rule for number language," "The end of word problems," "Cubeyness," "Cardinal and ordinal
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Oxford University Press
The world's largest university press, publishing 3,000 new books a year, including scholarly works in all academic disciplines, bibles, music, school and college textbooks, children's books, materials for teaching English as a second language, business
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P2S Games - P2S Information Systems Pvt. Ltd
Online games that challenge you to click your way to filling containers of liquids (Fill It Up), completing equations with operations (Equation), adding adjacent tiles to maximize their overall sum (Maximize), selecting operations between the 4s to make
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Panamath - Panamath.org
Have you ever tried to guess how many jelly beans are in a jar without counting? The Panamath test measures your number sense -- your intuitive recognition of numbers and their relationships -- and approximate number system (ANS) aptitude. Practice estimating
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The Paper Challeran - Ryosuke Ito & TOSS
Starting with a score of 1, trace a route through the Paper Challeran. Add to, multiply, or subtract from this score, as indicated at every edge along the way. Compete by registering scores online. Numbers around each block change every month. Find rules,
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paperfolding.com - Eric Andersen
Learn to fold origami from diagrams; read about the history of paper-folding, including the origin of the term "origami." The origami & math essay contains sections such as Origami, Geometry, and the Kawasaki Theorem; and Origami and Topology.
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The Partnership for 21st Century Skills
The Partnership for 21st Century Skills is a national organization that advocates for the integration of skills such as critical thinking, problem solving and communication into the teaching of core academic subjects such as mathematics, reading, science
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Pascal's Triangle: Number Patterns - Math Forum
Some history and an interactive exploration of number patterns and an exploratory Internet Web unit for elementary, middle school, and high school, with lessons, number pattern studies, and links to relevant sites on the Web.
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Pat's Math & Problem Solving Links - Pat McQuatty
Site recommendations from the math consultant for the Western Quebec School Board. See, in particular, Special Days (Hundredth Day of school, Math with the number 2000 - twenty suggested math activities for the year 2000). Also math-related links for
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Pattern Based Reason - Alan Selby
This book surveys rule and pattern based thought in daily life, society, science and technology. The first chapters show how reliable implication rules can be employed one at a time or one after another to arrive at conclusions. The middle chapters describe
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Patterns - Suzanne Alejandre
Links to Web sites with patterns. Students look through the pages and answer these questions: How do natural patterns influence us? How do patterns help us to solve problems? Can you put elements of a pattern into an order that can be measured? that
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Pat Thompson's Home Page - Patrick W. Thompson
Research on students' development of algebra and calculus ideas in grades 3-16, on the nature of multiplicative reasoning and its role in learning sophisticated mathematical ideas, and on teaching and learning statistical and probabilistic reasoning.
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